Vehicle occupant weight sensing systems are useful in connection with air bags and other pyrotechnically deployed restraints as a means of characterizing the occupant for purposes of determining whether to allow or suppress deployment of the restraints. For example, it is generally desired to allow deployment for an adult, and to suppress deployment (or reduce deployment force) for a child. However, it has been found that a child occupant can produce a static weight reading similar to that of a small (5th percentile) female adult due to variations seat belt tension and the orientation of the occupant on the seat, for example. In other words, the static weight readings for a child occupant and a small adult occupant statistically vary over first and second ranges due to system variability, and there can be some amount of overlap between the first and second ranges under certain conditions. Fortunately, the range of variability is substantially reduced in the case of dynamic weight readings (i.e., the variation of the weight reading), and the dynamic variation has been used to more reliably characterize the seat occupant for purposes of determining whether to allow or suppress restraint deployment. For example, in the U.S. Pat. No. 6,246,936 to Murphy et al., issued on Jun. 12, 2001, and assigned to the assignee of the present invention, the dynamic variation is used to distinguish a tightly cinched child seat from an adult; and in the U.S. patent application Ser. No. 09/895,742, filed on Jul. 2, 2001, and assigned to the assignee of the present invention, the dynamic variation is normalized with respect to acceleration of the vehicle to compensate for the effects of operating the vehicle on a rough road surface.